CN-121979124-A - Lightweight thermal power plant oxygen control method and system

CN121979124ACN 121979124 ACN121979124 ACN 121979124ACN-121979124-A

Abstract

The application relates to a lightweight thermal power plant oxygen control method which is applied to a distributed control system of a thermal power plant and comprises the steps of dividing a plurality of continuous load operation intervals according to the load of the thermal power plant, acquiring historical optimal oxygen under each load operation interval based on an operation database, performing function fitting based on the corresponding relation between the load operation interval and the historical optimal oxygen, determining an optimal oxygen set value under the current load of the thermal power plant according to a fitting result, calculating a deviation value between the optimal oxygen set value and the real-time operation oxygen of a boiler, introducing the deviation value as correction bias into an oxygen set loop of the boiler air supply control system, and adjusting the oxygen. The method solves the problem of poor real-time and accuracy of oxygen regulation of the thermal power plant, and reduces the operation load and implementation cost of a control system while ensuring the control precision based on a lightweight control strategy of load partition and history optimal data fitting.

Inventors

DING YUMING
WANG YINGXIN
ZHOU CHENGYANG
WU XUECHONG
XU WEIQIANG
QU ZHANGLONG
LIU YAMIN
XU JING
JI LI

Assignees

华电电力科学研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20251217

Claims (10)

1. The method is characterized by being applied to a distributed control system of a thermal power unit, and comprises the following steps: dividing a plurality of continuous load operation intervals according to unit load, and acquiring historical optimal oxygen amount under each load operation interval based on an operation database; Performing function fitting based on the corresponding relation between the load operation interval and the historical optimal oxygen amount, and determining an optimal oxygen amount set value under the current load of the unit according to a fitting result; And calculating a deviation value between the optimal oxygen set value and the real-time running oxygen of the boiler, introducing the deviation value serving as a correction offset into an oxygen set loop of a boiler air supply control system, and adjusting the oxygen.
2. The method of claim 1, wherein the obtaining a historical optimal oxygen amount for each of the load operating intervals based on an operating database comprises: Obtaining an optimal boiler efficiency value from an operation database, and boiler operation oxygen corresponding to the historical optimal boiler efficiency value; And taking the boiler operation oxygen amount as the historical optimal oxygen amount in the load operation interval.
3. The method according to claim 1, wherein the performing a function fit based on the correspondence between the load operation interval and the historical optimal oxygen amount, and determining the optimal oxygen amount set value under the current load of the unit according to the fitting result comprises: performing function fitting based on the corresponding relation between the load operation interval and the historical optimal oxygen amount to generate an optimal oxygen amount setting function in a full load range, wherein the function fitting is linear interpolation fitting, and the optimal oxygen amount setting function is a piecewise linear function; and obtaining a current optimal oxygen setting value through the optimal oxygen setting function according to the current load of the unit.
4. The method of claim 1, wherein introducing the deviation value as a correction offset into an oxygen amount setting circuit of a boiler blow control system, adjusting the oxygen amount comprises: Generating a control instruction of an oxygen setting loop according to the deviation value, the real-time operation oxygen amount, and preset adjustment rate constraint and amplitude constraint to instruct the oxygen setting loop to adjust the air supply amount so that the real-time operation oxygen amount of the boiler approaches to the optimal oxygen amount set value.
5. The method according to claim 1, wherein the method further comprises: respectively acquiring boiler operation parameters before and after oxygen adjustment; Determining the boiler operation efficiency before oxygen amount adjustment according to the boiler operation parameters before oxygen amount adjustment; Determining the boiler operation efficiency after the oxygen amount adjustment according to the boiler operation parameters after the oxygen amount adjustment; Comparing the boiler operation efficiency before and after the oxygen amount is adjusted, and generating an abnormal adjustment early warning signal and/or a re-optimizing signal under the condition that the boiler operation efficiency after the oxygen amount is smaller than the boiler operation efficiency before the oxygen amount is adjusted.
6. The method of claim 5, wherein the method further comprises: Acquiring a first historical optimal boiler efficiency value of a load interval corresponding to the current load and a first boiler operation oxygen amount corresponding to the first historical optimal boiler efficiency value from the operation database; carrying out weighted summation on the first historical optimal boiler efficiency value and the boiler operation efficiency after the oxygen amount is adjusted to obtain an optimal efficiency update value; Carrying out weighted summation on the first boiler operation oxygen amount and the optimal oxygen amount set value to obtain an optimal oxygen amount updated value; And in the operation database, replacing the first historical optimal boiler efficiency value with the optimal efficiency updating value, and taking the optimal oxygen amount updating value as the boiler operation oxygen amount corresponding to the optimal efficiency updating value.
7. The method of claim 2, wherein the obtaining a historical optimal oxygen amount for each of the load operating intervals based on an operating database comprises: Extracting all steady-state operation data points located in any load operation interval from the operation database under the condition that the operation database does not directly store the historical optimal boiler efficiency value; screening out a target data point with highest boiler efficiency from steady-state operation data points meeting preset constraint conditions, and taking the efficiency value of the target data point as a historical optimal boiler efficiency value; acquiring a boiler operation oxygen amount corresponding to the historical optimal boiler efficiency value, and taking the boiler operation oxygen amount as the historical optimal oxygen amount in the load operation interval; The preset constraint condition comprises at least one of the following conditions that the emission concentration of nitrogen oxides reaches a preset standard, the emission concentration of carbon monoxide is lower than a preset concentration threshold value, the temperatures of main steam and reheat steam are in a preset temperature range, and a burner flame stabilizing signal is normal.
8. Lightweight thermal power plant oxygen control device, its characterized in that, the device sets up in the distributed control system of thermal power generating unit, the system includes: the data acquisition module is used for dividing a plurality of continuous load operation intervals according to the unit load and acquiring historical optimal oxygen amount under each load operation interval based on an operation database; the fitting module is used for performing function fitting based on the corresponding relation between the load operation interval and the historical optimal oxygen amount, and determining an optimal oxygen amount set value under the current load of the unit according to a fitting result; the adjusting module is used for calculating the deviation value between the optimal oxygen quantity set value and the real-time running oxygen quantity of the boiler, taking the deviation value as a correction offset, introducing the correction offset into an oxygen quantity set loop of the boiler air supply control system, and adjusting the oxygen quantity.
9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor, when executing the computer program, implements the lightweight thermal power plant oxygen control method of any one of claims 1 to 7.
10. A storage medium having stored thereon a computer program, wherein the program when executed by a processor realizes the lightweight thermal power plant oxygen amount control method according to any one of claims 1 to 7.

Description

Lightweight thermal power plant oxygen control method and system Technical Field The application relates to the technical field of industrial intelligent control, in particular to a method and a system for controlling the oxygen content of a lightweight thermal power plant. Background In the operation of the existing thermal power generating unit, the control of the boiler oxygen mainly depends on a set value based on the unit load to form a loop. The loop usually adopts a classical PID control strategy, and the oxygen set value is mostly a fixed curve preset according to a single load variable, however, the fixed curve cannot reflect the time-varying characteristic of the actual operation of the boiler, and often causes the oxygen set value to deviate from the current actual optimal working condition. Meanwhile, accurate acquisition of boiler efficiency is a precondition for implementation of energy-saving closed-loop control. At present, a production primary region (DCS) of a thermal power plant generally does not have a function of performing complex and multi-parameter boiler efficiency real-time calculation, so that a closed-loop control circuit targeting 'real-time optimizing efficiency' cannot be constructed based on control logic of the production primary region. On-site operation is mainly regulated by depending on operation experience and history curves, has hysteresis and subjectivity, and is difficult to systematically and automatically excavate and lock the optimal oxygen amount operation points under different loads. Disclosure of Invention The embodiment of the application provides a lightweight thermal power plant oxygen control method, a lightweight thermal power plant oxygen control system, electronic equipment and a lightweight thermal power plant oxygen control storage medium, which at least solve the problem that the real-time performance and accuracy of thermal power plant oxygen regulation in the related art are poor. In a first aspect, an embodiment of the present application provides a lightweight thermal power plant oxygen amount control method, where the method is applied to a distributed control system of a thermal power unit, and the method includes: dividing a plurality of continuous load operation intervals according to unit load, and acquiring historical optimal oxygen amount under each load operation interval based on an operation database; Performing function fitting based on the corresponding relation between the load operation interval and the historical optimal oxygen amount, and determining an optimal oxygen amount set value under the current load of the unit according to a fitting result; And calculating a deviation value between the optimal oxygen set value and the real-time running oxygen of the boiler, introducing the deviation value serving as a correction offset into an oxygen set loop of a boiler air supply control system, and adjusting the oxygen. In some embodiments, the obtaining, based on the operation database, a historical optimal oxygen amount for each of the load operation intervals includes: Obtaining an optimal boiler efficiency value from an operation database, and boiler operation oxygen corresponding to the historical optimal boiler efficiency value; And taking the boiler operation oxygen amount as the historical optimal oxygen amount in the load operation interval. In some embodiments, the performing function fitting based on the correspondence between the load operation interval and the historical optimal oxygen amount, and determining the optimal oxygen amount set value under the current load of the unit according to the fitting result includes: performing function fitting based on the corresponding relation between the load operation interval and the historical optimal oxygen amount to generate an optimal oxygen amount setting function in a full load range, wherein the function fitting is linear interpolation fitting, and the optimal oxygen amount setting function is a piecewise linear function; and obtaining a current optimal oxygen setting value through the optimal oxygen setting function according to the current load of the unit. In some embodiments, introducing the deviation value as a correction offset into an oxygen amount setting circuit of a boiler air supply control system, and adjusting the oxygen amount includes: Generating a control instruction of an oxygen setting loop according to the deviation value, the real-time operation oxygen amount, and preset adjustment rate constraint and amplitude constraint to instruct the oxygen setting loop to adjust the air supply amount so that the real-time operation oxygen amount of the boiler approaches to the optimal oxygen amount set value. In some of these embodiments, the method further comprises: respectively acquiring boiler operation parameters before and after oxygen adjustment; Determining the boiler operation efficiency before oxygen amount adjustment according to the boiler operation par